1. Field
This application relates to a signal processing device without a mechanical switch for an ON/OFF operation.
2. Description of Related Art
A small amount of electric current is in constant flow through a human body since the human body is a conductive material. Accordingly, various physiological characteristics may be measured by sensing an electric current or a change in the electric current caused by an external stimulation applied to a human body.
This principle enables a biopotential to be measured. Examples of a biopotential include an electrocardiography (ECG) potential, an electromyography (EMG) potential, an electroencephalography (EEG) potential, a galvanic skin response (GSR), electrooculography (EOG), a body temperature, a pulse, a blood pressure, and a body motion. A signal processing device is used to sense a biometric signal or a change in a biometric signal.